Variable-speed governor for motionpicture cameras



Nov. 27, 1945. ss 2,389,932

VARIABLE SPEED GOVERNOR FOR MOTION PICTURE GAMERKS Eiled Feb. 7, 1944 I mmvron. 7/70/7705 A 19255 BYg;

Patented Nov. 27, 1945 VARIABLE-SPEED GOVERNOR FOR MOTION- PICTURE GA MERAS Thomas I. Bess, Chicago, 111., assignor De Vry Corporation, Chicago, 111., a corporation of Illinois Application February '1, 1944, Serial No. 521,341

, 1 Claim.

This invention relates to certain new and useful improvements in motion picture cameras, and more specifically to ahvariable speed governor therefor and has among its principal objects the provision of an improved structure of this character which will be highly eflicient in use and economical in manufacture.

In most motion picture cameras there is employed a spring motor of a well-known type and desi n. This motor, for picture recision, should during operation run at a uniform speed, otherwise the results will be unsatisfactory picture photography. It is therefore one of the principal objects of this invention to provide in such a camera provisions for controlling and adjusting the speed or the spring motor by means of a single speed governor which is variable in adjustment to bring about. the desired speed for best photography.

A still further object of the invention is the provision of means for preventing the spring motor from running wild.

Another object of the invention is the provision for manually adjusting the governor from the exterior of the camera housing.

Other objects will appear hereinafter.

The invention consists in the novel combination and arrangement of parts to be hereinafter described and claimed.

The invention will be best understood by reference to the accompanying drawing showing thepreferred form 01' construction, and in which:

Fig. 1 is a side view of a camera with parts broken away, showing my improved variable speed control;

Fig. 2 is an enlarged fragmentary sectional view of the variable speed control embodied in my invention; and

Fig. 3 isa fragmentary detail view taken substantially' on line 3-3 of Fig. 1.

Many forms of construction-may be provided for'accomplishing the various objects of my invention. The drawing (Figs. 1 to 3 inclusive) illustrates my preferred form of construction. In this connection a camera is indicated generally at l8 and comprises side walls ll and|2 and walls l3. This camera further includes a lens structure I4 of a well-known form and construction.

This lens structure does not constitute any art 'ofthe presentinvention. V V

Arranged within the housing l5 provided by the walls ll; l2 and i3 is a spring motor It. This motor I8 is of a well-known construction used in cameras of the type shown for driving the film.

intermediate gear 2|.

I! meshing with a pinion I8 mounted on a shaft l3. On the hub of the pinion I8 is fixed an This gear 2| meshes with a pinion 22 fixed to a shaft 23. One end of this shaft 23 is journalled in the wall i2 while the opposite end of the shaft is Journailed in a suitable bearing 24 carried as at 25 by a partition 26.

A thrust washer 21 is mounted on the bearing 25 and bears against a roller bearing 23' which in turn bears against a disc 28 having free rotatlon on the bearing 24. This disc 28 is provided on one face with a plurality of spaced circular ooves 29.

Fixed to the shaft 23 isa friction disc 30. This disc 38 is spaced from the grooved disc 28. Between these discs 28 and 30 is a friction wheel 3| having a flange 32 thereof adapted to en age in the groove 23 and also bear against th face of the friction drive disc 38.

This friction wheel is slidable longitudinally upon a stud 33 and has connection therewith by means of rib and groove connection 34 whereby the friction wheel may be moved longitudinally on the stud but must rotate therewith.

This stud is formed as a part of a shaft 35 of the governor 38 of a well-known construction including the balance weights 31 and an adjustable screw 38 the latter serving as a brake in its engagement with an adjacent brake disc formed as an integral part of the governor sleeve 39, as best shown in Fig. 2.

The brake disc is shown at 39' and operates against a spring 35' serving to resist the movement of the sleeve 39 by action of the weights 38 and 31.

This governor may be of any well-known construction and includes a frame 40 pivotally supported upon pintle M carried by bracket 42 secured to the wall i2.

To complete the invention I provide in the wall ii an elongated opening 43; Secured to the wall I I and having an opening 44 registering with the opening 43 is an escutche'on plate 45 having indicia 48 thereon to indicate the speed of rotatlon of the spring motor.

Pivoted to the wall i2 as at 41 is an arm 48.

One end of this arm 48 carries a clamping screw 49 by which the arm 48 may be secured in an adjusted position: with respect to the plate 45. The other end of the arm 48 is provided with a yoke 5|I'Whl0h engages in a, groove 5lprovided by the friction'wheel 3|. The arrangement is such that by loosening the clamping screw 48 the arm 43 may be adjusted to change the posi- Associated with this motor i3 is aring gear tion of the friction wheel at with respect to the grooved disc 28 and the face of the friction drive wheel 30.

Should the friction wheel be adjusted in the groove nearest the axis of the shaft 23 it is clear that the speed of rotation of the governor shaft 35 will be faster than would be its speed were the friction wheel 32 adjusted in the outermost of the grooves'29, with the result that thespeed of rotation of the governor will be proportionately increased over the speed of the spring motor, resulting in quicker movement of the governor sleeve 38 to bear the brake disc thereof against the brake screw 38. In this manner a uniform speed is maintained and may be varied at the will of the operator to meet changing conditions during the act of photographing.

While I have illustrated and described the claim as new and desire to protect by Letters Patcut is: a

Means for controlling the speed of a spring motor of a motion picture camera comprising a supporting structure, a shaft rotatably carried by said structure, means operatively connecting preferred form of construction for carrying my said shaft to said spring motor, opposed discs on said shaft, one of said discs being freely rotatable with respect to said shaft and provided with a plurality of facial grooves, means fixedly securing the other of said discs to said shaft for rotation therewith, a friction wheel disposed between said discs and frictionally engaging the face of the disc fixed to said shaft and adapted to selectively engage the grooves of the freely rotatable disc, a governor, said governor including a governor shaft carrying said friction wheel and having means to permit said wheel to be moved longitudinally with respect thereto, a spring-controlled governor sleeve on said governor shaft and having a brake disc, and a brake screw adapted to be engaged by said disc, in combination with means for moving said friction wheel relative to said overnor shaft.

THOMAS I. RESS.' 

